This invention relates in general to devices for protecting caster wheels from running against floor debris and, more particularly, to a skirt assembly mounted on a swiveling caster wheel to move and swivel with the wheel to sweep floor debris away from the caster.
Many structures, such as shopping carts, creepers used by auto mechanics, industrial carts, chairs, tables and the like are mounted on casters for ease of movement. Where there is debris such as pebbles, nuts, bolts, manufacturing scrap, or other small objects on the floor, the smooth movement of castered structures will be impeded. The user will have to stop, back up and attempt to change the path of movement to avoid the object. In addition to the resulting annoyance, where the structure is a loaded, high center of gravity shopping cart, electronic equipment cart, etc., the cart may tip over, damaging any items being transported and possibly injuring persons in the area. Where the structure is a swivel chair or a castered stool of the sort often used by industrial assemblers, the chair or stool may tip over, injuring the occupant.
In certain environments, such as textile mills, barber shops, carpeted areas and the like, strand materials such as threads, fibers, hairs are often scattered over the floor. As a castered structure is moved on such floors, in time the strands will accumulate at the swivel hub, getting between the caster and caster housing and between the axle and wheel. This makes moving the castered structure increasingly difficult and eventually can lead to tipping of the structure. Further, such strands are difficult and time consuming to remove from the caster.
Attempts have been made to develop caster accessories to reduce or eliminate these problems. Typically, a large diameter skirt having a wide housing within which the caster can swivel is fastened to the structure, as disclosed by Humphreys in U.S. Pat. No. 2,471,958 and Katcher in U.S. Pat. No. 2,046,386. A brush extends from the skirt into contact with the floor to push debris ahead of the caster path. Most casters have the wheel axle offset from the swiveling axes, so that the caster is trailing as the structure is moved, for ease of movement, resulting in a very large diameter skirt.
Where the skirt is directly fastened to the structure, the particular skirt system must be designed into the structure when it is manufactured and cannot be conveniently added later. In addition, these specialized systems cannot be easily disassembled for cleaning or repair.
Solid walled shields have been provided for casters to push solid debris away from moving casters, such as are described by Rainville in U.S. Pat. No. 5,371,920 and Jones in U.S. Pat. No. 3,818,542. These have relatively large diameters, since the caster must swivel within them. Further, they tend to snag on changes in floor elevation, such as thresholds or expansion strips in concrete floors where floor level changes slightly across the strip, causing the very problems of tipping or stopping that the skirt was intended to overcome.
Others have attempted to prevent dirt, fibers, string and the like from accumulating between the wheel support and wheel or around the wheel axle by providing brushes that bear against the wheel as the wheel rotates. Typical of these are the brush systems disclosed by Turbyfill in U.S. Pat. No. 2,923,017 and by Smith in U.S. Pat. No. 3,744,080. While these systems may aid in keeping fibers, lint, hair clippings, etc. out of the caster, they do nothing to prevent the caster encountering and bing stopped by solid debris.
Thus, there is a continuing need for improved caster systems that sweep solid debris away from the path of a moving caster, keep strand like material from tangling a caster axle or housing, are easily assembled and disassembled, can be easily retrofitted into existing caster systems and are compact, light weight and unobtrusive.